build menu: reword the entries

build menu: reword the entries

- make more obvious first “Final” entry is not the best one
  by listing what it does (compared to others)
- mark the best one as recommended
- make obvious the “Final” builds do all the stages
- add low/medium notes within parenthesis
- make it less techy, list stages and options as word,
  also no need to list both “noSRGB” and “OLD LIGHTING”
- always start menu entries with Caps
- name file extension as it is produced (lowercase)
- explain better the -onlyents option
- use “Compile and convert” and “Convert” wording
  for exporting to ase/obj